The frontal lobe plays a key role in many higher cognitive functions including working memory, attention, planning, and abstract thought. Head trauma, degenerative diseases, strokes, and tumors can disrupt frontal lobe function. Impaired frontal lobe functioning also occurs in mental health disorders such as attention deficit disorder and schizophrenia. The proposed research seeks to enhance our understanding of the functional organization of the human frontal lobe, while providing a valuable research training opportunity for a young scientist. The goal of this research is to reveal the frontal lobe structures and mechanisms by which visual and auditory attention and short-term memory support cognition and perception. Many daily tasks, such as talking on the phone or reading in a noisy room, require the mind to attend to information in one sensory modality while ignoring distractors in another. Audition and vision have complimentary strengths and weaknesses, with vision having superior spatial resolution and audition having excellent temporal resolution. However, these two sensory modalities also provide independent pathways to encoding the same information (e.g., object recognition or language comprehension). Various regions in the occipital, temporal, and parietal lobes show a strong bias for processing either auditory or visual information; however, researchers have been less successful in identifying sensory modality differences in the frontal cortex, potentially due to its role in higher cognitive functions. This project involves a series of functional MRI experiments that manipulate the sensory modality and the content of relevant information to investigate the organization of the lateral frontal cortex. The proposed research will compare auditory and visual attention networks using direct contrasts of attention to auditory or visual stimuli among distractors presented in both sensory modalities. Functional connectivity analysis of auditory and visual networks will also be employed to reveal frontal lobe organization. Preliminary findings suggest multiple interdigitated auditory and visual network regions within the frontal lobe. It is hypothesized that these regions reflect the type of representation rather than the sensory modality, per se. To test this hypothesis, sensory modality (visual or auditory) and type of information (spatial or temporal) will be manipulated in attention tasks; we predict that different networks will be dynamically recruited depending upon the type of information being processed. Further experiments will manipulate the rules governing how subjects respond to a given stimulus in order to determine if different neural substrates are involved in processing complex decision rules in the auditory and visual modalities. The successful completion of this project will increase our understanding of the role of the modality of sensory input and information type when performing higher-level cognitive functions such as attention and understanding abstract rules.